> It's possible they managed to do some rudimentary multitasking with DESQview (or worse...) and so supported two whole users with each box. Does that mean they had to be at least 386s to do protected mode? Or was it virtual 8086 mode? I (fortunately) have forgotten the finer points of how that stuff used to work. I DO remember how damn crashy a box became when you ran it "under DV". Constant system freezes. Yep.

I don't recall DESQview to be all that crashy. I was aware of a number multi-line BBSes that used it (just in the 416). Some BBS software called out its use specifically:

* https://www.synchro.net/docs/multnode_config.html

* http://software.bbsdocumentary.com/IBM/DOS/OMEGA/

Also, a comment from someone whose uncle co-founded the company Quarterdeck:

* https://news.ycombinator.com/item?id=29396561#unv_29400530

Also, also, if anyone wants to simulate the old-school DESQview experience, perhaps try out "twin":

* https://opensource.com/article/20/1/multiple-consoles-twin

* https://github.com/cosmos72/twin